1. Technical Field
The invention relates generally to image processing systems, and, more particularly, to image processing systems for identification and verification of images of fingerprints.
2. Description of the Related Art
There are two classes of problems which are addressed by the present invention. The first class of problems involves situations where it is necessary to verify or authenticate an individual's identity. That is a person appears claiming a particular identity or attempting to access information which should only be released to a particular individual. It is important to be able to have some reliable means of verifying this individual's identity or at least confirming that this is the same person who initially registered with the system.
The second, more challenging problem occurs when it is important to ensure that a particular database contains only a single entry for any given individual. This occurs in the case of social services wherein one wishes to prevent individuals from collecting welfare under multiple aliases or in the case of identity card issuance. This identification problem requires that one be able to search a large database of individuals and determine whether this person is already the database. In the case where the database contains millions of individuals, this search is very challenging.
Much of the existing art in this area requires a linear search of the entire database. Using this approach, a full search of a database containing one million entries might require a comparison of the query individual's fingerprint(s) against each entry in the database, thus involving a million or more comparisons. In order to address this problem, much of the existing art uses filtering methods to classify fingerprints and individuals. For example, the database may be segmented by sex, race, approximate age, and fingerprint class. This effectively reduces the size of the database to be searched and consequently the amount of work that must be performed. However, any error in the initial classification leads to a missed identification.
Thus, there is a need in the art to provide for an improved, cost effective and efficient system for matching fingerprints stored in large databases.